Gov. Bill Ritter’s property-tax freeze will generate an estimated $2 billion more over 10 years than lawmakers were expecting when they approved it eight months ago, according to the latest calculations.

The revenue leap fired up Republican lawmakers — who were already calling the freeze an “illegal tax hike” — as the legislature convenes today for its 2008 session.

The freeze, which prevents local property taxes for schools from dropping, is now projected to result in nearly $3.8 billion in state money by 2017. That’s more than double the $1.74 billion estimated when lawmakers passed the governor’s proposal in May.

“It’s modern-day bank robbery,” said Rep. Cory Gardner, a Yuma Republican who requested the new estimate from the nonpartisan Legislative Council. “The fraudulent part of this is it’s done without a vote of the people.”

Ritter spokesman Evan Dreyer said estimates “can fluctuate greatly. That’s just the way the state budgeting process works.”

Ritter’s office disputes claims that the freeze is an illegal tax hike. The governor points out that in 175 of Colorado’s 178 school districts, voters decided to keep revenues over the amount allowed by the state constitution.

“Rep. Gardner thinks he has a political club to try to wield here,” said Dreyer. “He’s wrong.”

Independence Institute president Jon Caldara is suing the state over the freeze, saying it ignores a constitutional amendment requiring statewide voter approval for tax increases.

Before the legislature approved the freeze, state law was pushing local property-tax rates lower and forcing state taxpayers to pick up more of the bill in some wealthier school districts.

Money from the tax freeze goes into the state education fund, which will help pay for at-risk kids to go to preschool and full-day kindergarten. The extra revenue also freed up funds for higher education, Ritter said.

Dreyer said the mill levy stabilization is about “doing right by our children and our future” and “about keeping the state education fund from going bankrupt.”

House Speaker Andrew Romanoff, D-Denver, said he would have voted for the school-funding plan even with the latest revenue estimate. Also, he said 10-year economic forecasts are often off the mark.

“The political debate should be over — there was a vote of the people 175 times,” he said. “The opposition wants to keep going to the ballot until the people say no.”

Using the new estimate in a political game is unproductive, Romanoff said.

“It’s cute for Cory to play cops and robbers, but it doesn’t help any kids,” he said.

But Sen. Josh Penry, R-Grand Junction, said the new projections will have larger implications, perhaps shutting down talk of a tax proposal to fund health care or transportation.

“It should put a nail in the coffin of another tax increase in 2008,” he said.

While Penry said he didn’t think the “huge disparity” in revenue estimates was intentional, “the legislative economist and the governor’s economist deserve to be asked some very tough questions.”

Ritter said Tuesday that he doubted voters were ready for a tax proposal this year on health care, higher education or transportation.

The tax freeze was originally projected to generate $48 million in new state money this year. That number has climbed to $117 million, according to this week’s calculation.

The projection jumped with revised forecasts for inflation, student counts and property value assessments, according to the memo from Legislative Council.

The memo says mill levies in 116 districts remained at higher levels than they would have under the old law, creating $123.2 million in property-tax revenue.

The new law reduced levies in 30 school districts, lowering taxes by $5.4 million. It had no effect in 32 districts.

Caldara, who filed his lawsuit over the tax freeze last month, said he wasn’t surprised the estimate was off but said taxpayers “are going to become incensed.”

Caldara and Gardner said the underestimate is reminiscent of Referendum C, which suspends the state’s constitutional revenue limits for five years. State economists are predicting it will bring in $5.9 billion — $2.2 billion more than estimated when it was approved by voters in 2005.

Jennifer Brown is an investigative reporter for The Denver Post, where she has worked since 2005. She has written about the child welfare system, mental health, education and politics. She previously worked for The Associated Press, The Tyler Morning Telegraph in Texas, and the Hungry Horse News in Montana.

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